Methyltetrahydrofolate (5-MTHF): Patient Information & Safety Notes
Also known as L-methylfolate
Other names: 5-mthf, l-methylfolate, methylfolate
Methyltetrahydrofolate (5-MTHF, L-methylfolate) is the biologically active, methylated form of folate that is directly usable by cells without enzymatic conversion. It is available as a dietary supplement and, in some formulations, as a prescription medical food (e.g., Deplin) for individuals with MTHFR gene variants that impair folate metabolism.
In plain language
What 5-Methyltetrahydrofolate is used for
- Folate support in MTHFR gene variant carriers
- Homocysteine management
- Adjunct to antidepressant therapy (prescription medical food context)
Taking this medicine
How it is administered
- Oral capsule or tablet
Read before you decide
Risks and precautions
Risks and warnings
- Nausea, bloating, insomnia
- Headaches (at higher doses)
Who should not take it
- Epilepsy (high-dose folate may affect anticonvulsant efficacy)
- Pregnancy (take folate under provider guidance for correct dose)
Common questions
Patient questions
Should I take 5-MTHF instead of folic acid?
Individuals with MTHFR gene variants may have difficulty converting folic acid to its active form. 5-MTHF bypasses this conversion step. A licensed provider can order MTHFR testing and recommend the appropriate folate supplement or medical food.
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This information is educational — not medical advice.
This page is provided for general educational purposes and summarizes publicly available data from sources such as the U.S. Food & Drug Administration. It is not a substitute for the judgment of a licensed clinician and should not be used to start, stop, or change any medication. It may be incomplete or out of date, and individual circumstances vary. Always talk with your prescriber or pharmacist about your specific medications and health conditions. If you think you may have a medical emergency, call 911.
Sources & References
Learn more about where our data comes from and how we write and review medical content.